Kissing isn’t just romantic—it’s a major bacterial exchange. A 10-second intimate kiss transfers about 80 million bacteria through saliva, shaping partners’ oral microbiomes. The oral microbiome includes diverse bacteria on the tongue and in saliva, like Streptococcus, Lactobacillus, and Bifidobacterium, which support digestion and immunity. Studies show couples who kiss frequently (9+ times daily) develop […]